Finding the Third Proportional to 67,178 and 90,921

Step by Step Solution

1. Step 1: Write the proportion equation
   67,178 : 90,921 = 90,921 : x
2. Step 2: Convert to fraction form
   67,178/90,921 = 90,921/x
3. Step 3: Cross multiply
   67,178x = 90,921 × 90,921
4. Step 4: Simplify right side
   67,178x = 8,266,628,241
5. Step 5: Solve for x
   x = 8,266,628,241/67,178
6. Step 6: Final answer
   x = 123,055.59